Stoker



Nov. 13, 1928.

M.- J. WIGHTMAN STOKER Filed May 24, 1926 Patented Nov. 1.3, 1928.

UNITED STATES PATENT orrlca.

KER-LEI. WIGHTHAN, OF WEST NEW BRIGHTON, NEW YORK, ASSIGNOR TO DOMESTIC STOKER COMPANY, OF NEW YORK, N. Y., A. CORPORATION OF DELAWARE.

STOKER.

Application filed May 24, 1926. Serial No. 11,182.

This invention relates to coal stokers and particularly to stokers intended for use in furnaces forheating residences. In my Reissue Patent No. 16,139, August 11, 1925, I

' of anthracite. In burning certain types of coal, however, it has been found that there is a tendency for the particles of coal to fuse together near the top of the fire pot and thus produce a solid core at that point which interferes with proper combustion. In order to burn efficiently the coal which makes up this fused or caked core, it is necessary to break up the cake into small particles in order that the air of the blast may cpme into intimate contact with each partic e.

My present invention has todo primarily with the provision of. means for breaking up, at intervals, the fused or caked core that may be formed as above described. Mere agitation of the fuel bed has been found to beineifective. Indeed, so'far as I'have been able to determine, the only way in which this core may be broken up effectively is by sub.- jecting it to the .blow of'a heavy object. Accordingly, as will hereinafter be pointed out in detail,-I have devised an attachment for stokers of the general class under consideration', which attachment includes a heavy tamper or baflie with means for dropping it at intervals on to the caked core within the 'fire pot. The hammering of the core by 1 means of this tamper keeps the core broken up and thus brings about com lete combustion of all of the fuel that is ed to the fire pot. I In the drawing, Fig. 1 is a side elevation partly in section, showing'iny attachment applied to a stoker 'of the general type of at illustrated in my reissue patent refe I ed to above, and Fig. 2 is an'end view on an enlarged scale, showing partof the hopper construction and the mechanism for actuatingzthe tamper.

' eferrin to this drawing, I'shall first explain bri y the construction and operation of the stoker itself. The hopper 10, which is adapted to receive the fuel, is shown only in part. The fire pot 11 is located within the furnace F. 'Between the fire pot and hopper is the feeding passage 12 and the air blast passage 13. Within the feeding pas- 3 sage is located the feeding worm 14 adapted to be power driven by means hereinafter described, to feed coal from the hopper intothe bottom of, and through, the fire pot 11.

Through the draft passage 13 and the perforations 15 in the fire pot a forced draft fire.

The above described mechanism, perse,

forms no part of my present invention. I

shall now proceed to describe the attachment to which my present invention is directed.

This attachment includes the baffle or tamper 16} which is made of some refractory material, and is normally held above the fire lever being pivoted at 18 ton, suitable support 19 secured to the fire pot. The other end of this lever 17 is connected by means of the link 20 to one arm of the bell crank 21, to the other arm of which is connected the link 22. This link '22 is connected through the device 23 (which is in the nature of a universal joint) to the slidably-androtatably mounted rod 24.

Means which will now be described are provided for periodically moving the rod 24 from a blower (not shown) is applied to the to the left and thus raising the tamper 16,

and for releasingthe rod 24 and thus permitting the tam er to fall by gravity onto the fire, to bre up any fused cake which ma have formed.

tep-by-step motion is imparted to the feeding worm 14 and-shaft14 by any suitable power driven means, such as the pawl and ratchet mechanism 27, 28, 29. Secured to this shaft 14 and partaking of its rotationis the cam 30. The cam roller 31 which cooperates with this cam. is carried by the. bifurcated arm .32 which is secured to the rod 24. Also secured to this rod is the cam surface 33 which cooperates with the'sta onary; cam face -34 mounted on the hopper frame. 1

The parts are shown in the drawing inthe is repeated.

position which they occupy when the rod 24 is at the left hand limit of its travel and the tamper 16 elevated to its extreme height. That i's,-the cam roller 31 is at the highest point of the cam 30. .In moving to that position it has caused the rotation of the cam surface 33, and the latters cooperation with cam surface 34 has resulted in moving the rod 24 to the left. Further rotation of the cam 30 results in the cam roller 31 dropping toward the center of rotation of the cam. This releases the rod 24 for' movement to the right and permits the tamper 16 to fall on the fire. This-cycle of operations It will be noticed that the bottom portion of the tamper 16 is in the form of an inverted truncated cone. As the result of this design the dropping of the tamper on to the fire has a tendency to accelerate the movement of the fuel, with which it comes in contact, in a radial direction. The result is that the dropping of the tamper head not only breaks up whateverfused or caked core may have been formed, but also moves the fuel to a position where it comes into direct contact with the air blast. -As the result, very complete combustion is obtained.

While I have illustrated my present invention in connection with one particular type of stoker, it is, of course, understood that it may be usedwith equal effect upon any type Where the problem of the formation of fused cakes is met.

The terms and expressions which I have employed are used as terms of description and not of limitation, and I have no intention, in the use of such terms and expressions, of excluding any mechanical equivalent of the features shown and described, or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

What I claim is: 1. Inadevice of-the character described, a fire pot ofthe underfeed-type having outwardly flared perforated edges, mea11s for feeding fuel into said fire pot, means for supplying air under pressure to said fire pot through'the perforations adjacent the edges thereof, a tampering member, and means for periodically lifting and-releasing said member to permit it to drop onto the fuel in-the fire pot to break up any fused cakes of fuel that may have been formed therein, said member being tapered so that it also forces fuel particles toward the draft supplying perforations.

2. In a device of the character described, a fire pot of the underfeed type, means for feeding fuel into said'fire pot, and means for breaking up fused masses forming in the fire pot comprising a tamping member and means for periodically raising and dropping said tamping member.

3. In a device of'the character described, a tire pot of the underfeed type, means for feeding fuel into said fire pot, a tamping member and means for periodically actuating said tamping member to break up fused masses forming in the fire pot and to move parts thereof toward the side of the fire 'pot'.

4. In a device of the character described, a fire pot of the underfeed type, means for feeding fuel into said fire pot and means for breaking up fused masses forming in the fire pot comprising a tamping member, the under surface of which is in the form of an inverted truncated cone, and-means for intermittently raising and dropping said tamping member.

MERLE J. WIGHTMAN: 

